Silo



March 11, 1930. J. R. RBERTS sILo Filed Nov. 26, 192s u a I D Patented Mar. 11, 1930 PATENT OFFICE JAMES RUSSEL ROBERTS,

OF LINCOLN, NEBRASKA SILO Application filed November 26, 1928.

My invention relates to silos and similar storage receptacles and especially to storage receptacles such as are used on the farm.

One object of my invention is the provision of a silo or other' storage receptacle which is wholly unaffected by the shrinkage and the expansion of the wood forming its walls.

Another object of my :invention is the provision of a structure which cannot be blown over when the silo is either filled or empty.

It is also my object to provide a verv efiicient permanent silo which can be built at a relatively low cost. Y

Having in view these objects and others which will be pointed out in the following description, I will now refer to the drawings, in which Figure 1 is a view in vertical section through the silo and through its anchor or retaining wall.

Figure 2 is a transverse section through a portion of two planks showing particularly the oint between the planks and showing also the concrete retaining` wall and the lining between the planks and the concrete retaining wall.

Figure 3 is a transverse sectional view showing the manner in which the planks are secured to the hoops.

Figure 1 is a fragmentary enlarged hori` Zontal section taken through a portion of the side wall of the silo.

The silo consists of a plurality of vertically positioned planks 10 in polygonal or circu-A r lar form and bound together by means of hoops 11 and anchored to a concrete retaining wall 12. The planks l0 are beveled on their inner sides at their edges as shown in Figures 2 and 3 so as to form V shaped notches at the joints. These notches are closed by means of strips 13 in wedge form which are secured in place by bolts 131 or other suitable means. Some of the hoops 11 are made of channel iron or other material with flat surfaces contiguous to the planks 10. Each plank is individually secured to each hoop by any suit-able fastening means such as a bolt 14 and nut, the nut beingjpreferably on the outside. At its lower extremity "o the silo wall is surrounded by a concrete re- Serial No. 321,962.

taining wall to which the silo is secured by means of bolts 15. The silo wall is preferably separated from the concrete retaining wall by means of one or more layers 1G of building or tar paper or the like.

The method of erecting the silo may be varied but in my preferred construction an excavation is rst made and the silo is erected with its bottom resting on the surface of the soil in the excavation. The outer surface of the lower end portion of the silo is then covered with roofing paper or any suitable nilar material and the bolts 15 are inserted l'ihrough the roofing paper and through the planks 10. Each plank is provided with one or .more bolts 15 and the bolts are so inserted that the bolt heads will be on the outside and at some distance from the planks. The con crete w'all 12 is then formed by pouring concrete into the excavation around the silo wall, the building or roofing paper preventing the concrete from adhering to the wood of the planks 10. After the concrete has set, thc nuts may be tightened on the bolts 15 on the inner side of the silo wall and the strips 13 may be secured in place. In the initial as`| sembling of the planks 10 spaces are left at the joints to allow for the 'expansion of the wood when it absorbs moisture either from the silage or from the atmosphere. The planks 10 may be beveled at any suitable angle but the angle of the wedge block should correspond with the angle of the bevel.

It will be readily apparent that the pressure of the silage against the wedge strips 13 Se will force them into the notches at the joints between the planks 10. Plastic cement may be used back of the strips to `herinetically seal the joints. At the same time the planks 10 will absorb moisture from the silage and they will thus swell and close the gaps beween them. In the storage of silage or other wet product the swelling of the wood will close the oints so Vtightly that no air or water will creep past the wedge strips and through the joints. Vhen the silo is empty, the conditions are just reversed and a rapid shrinking` of the wood takes place specially in the suinmer weather during which the silo is empty. Each joint then presents a large open gap and 100 the Wedge strips also will be found to be spaced away from the walls of the notches slnce there is no pressure back of them to seat them tightly in the notches. Each plank, however, is individually anchored to each hoop and to the concrete retaining wall so that even though there are large gaps at the oints,`the silo as a Whole will retain its form.

n the prior silos when empty, the wood staves shrink and the hoops become loosened. The silo then can be twisted or tipped over easily by the wind, for the rigidity of the lank is not used to help make the silo stand 1n a vertical position. In order to blow my silo over, the planks would have to be broken olf by the wind. The channel irons bind them all together, which makes them have the effeet of bracing each other. The silo built as above described will stand more wind pressure than any other buildings on the farm whereas prior built stave silos have a great tendency to blow down. lVhen once built, the Silo will shrink or swell but it has no eiect on the silo and there are no hoops to tighten after the shrinking of the silo.

The silo as above decribed is admirably adapted for repairs should any of the planks rot out or become broken or damaged. Since each plank is individually secured to both the hoops and the concrete retaining wall, it may be individually detached and replaced by a new plank. The nuts on the bolts let and 15 are all in the most easily accessible positions. Such breakage, however, or other damage to the planks is not liable to occur except through carelessness or accident. As a precautionary measure to facilitate the removal of a plank, it is advisable when erecting the silo to treat all bolts and nuts with tar. oil or other substances which will prevent rusting.

My initial and primary object is to provide a. silo construction but it is obvious that the structural principles herein described are applicable to other storage containers. The structure would have identically the same advantages if it were used as a water tank as it has in its use as a silo. Wheat or other grains may be stored in the structure and the pressure of these grains is great enough to force the wedge strips 13 into tight relation in the notches at the joints between the planks l0. The height and diameter of the structure are governed entirely by the specific use to which the structure is to be put. In general, the diameter of the structure as a silo depends on the rate at which the silage is to be used While the height of the structure depends largely on the amount of silage required for the seasons feeding. If the structure is to be used as a. water tank, the quantity of water as well as the necessary pressure must be considered in determining the diameter and the height of the water tank.

Some farmers prefer what is commonly called a trench silo, built horizontally on the ground. For such silos, vertical staves would be used with the same joint between planks and having all olf the same general lul-vain tages inherent in the construction of the ver spaced apart planks, hoops enclosing the planks to hold the same in circular order, nd planks having beveled edges at their inner sides providing deprcff-tsions at the adjacent edges of the planks, and wedge stri ps Y seated in the depressions adapted to be forced outwardly toward the beveled edges to seal the joints between the adjacent planks.

Q. A silo, comprising an annular concrete retaining wall adapted to be enibeilded in the .l

soil, a plurality of vertically positioned planks, fastening means for individually and releasably securing the lower ends ot the planks to said retaining wall against the inner surface thereo't, a plurality ot' hoops surrounding said silo and releasably secured to said planks, said planks being` beveled on their inner edges to provide notches at the meeting?? edges thereof and wedge stri ps loosely secured to said hoops and seated withinthe notches between contiguous planks,said wedge strips being adapted to be forced by the pressure of the silage into intimate contact with the edges of said planks to close the joints therebetween.

In testimony whereof I allix mv signature.

JAMES RUSSEL ROBERTS. 

